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enzymes Free essay! Download now

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Downloads to date: N/A | Words: 1231 | Submitted: 22-Jan-2013
Spelling accuracy: 98.5% | Number of pages: 3 | Filetype: Word .doc

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enzymes essay previewenzymes essay previewenzymes essay preview


this essay is about the use of enzymes and how the play an important role in the body


Enzymes are proteins that speed up, or catalyze, the rate of reactions in the human body without added energy. Enzymes work by bringing together two or more molecules called substrates so that they can interact and become a new molecule, called the product. Enzymes also hold products in place so that they can be broken down again into their constituent substrates. There are two basic characteristics of all enzymes. First, enzymes speed up the rate of a reaction without being used up or damaged. As long as ideal physiologic conditions are maintained, an enzyme can be recycled infinitely. Second, enzymes accelerate chemical reactions without changing the chemical equilibrium. Imagine you have two halves of a plastic Easter egg. You put the halves, or substrates, together to make a whole egg, or product, then take them apart. If you were an enzyme, the speed with which you put the halves together and take them apart would be the same.
An enzyme has an area called an active site to which only one type of substrate will bind. An old, simplified explanation was that a substrate fits in its enzyme like a key in a lock. Now scientists know that the interaction between enzymes and their substrates is much more complicated. After the substrate attaches to the active site, the enzyme changes shape to fit the substrateWithout enzymes, physiologic reactions would still occur, just in slow motion. For instance, without the enzyme carbonic anhydrase, the reaction by which carbon dioxide is transferred from cells to the blood would happen 107 times more slowly. Without carbonic anhydrase, carbon dioxide would build up in somatic tissues rapidly -- a consequence incompatible with life.
Thousands of enzymes are at work in the human body in every organ, tissue and cell. An enzyme called amylase begins the digestion of starches in your mouth, while peptidase helps with the digestion of proteins. Sucrase breaks down sugar into glucose and fructose. In muscle cells, the enzyme glycogen phosphorylase breaks down glycogen into glucose in response to the hormone epinephrine. This gives the muscle cells energy for a "fight or flight" response.

In the experiment, I will have to keep the concentration of enzymes
the same, because if the concentration of enzymes increases, it will
affect the enzymes action, hence speeding up the reaction, but if
decreased, the reaction will also decrease because, the substrate have
less chance of binding to an enzyme because the enzymes concentration
has been reduced. So I will have to keep the concentration of enzymes
the same for all the reactions, or if not I will have to change the
reaction, for all the other reactions to be the same, so that the
experiment will remain fair. ...

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